An ignition system of the above-described type is described in U.S. Pat. No. 3,881,458, assigned to the assignee of this application, to which U.S. Pat. No. Re. 29,862, and German DE-OS No. 22 44 781 corresponds. In the known ignition system a Schmitt trigger circuit is connected on the input side with the output of an inductive signal generator. The output voltage of the inductive signal generator increases with increasing speeds. The output of the trigger circuit in the known apparatus is connected to the input of a control stage which includes a transistor and a storage element. The output of the control stage in turn controls a driver stage whose output controls the output stage of the ignition system, namely an electronic switch constituted by a Darlington transistor circuit which is connected in series with the primary winding of the ignition coil. In this system, the energy stored in the storage decreases with increasing engine speed so that the ratio of conductive to blocked time of the interrupter switch increases with increasing engine speed. However, the increase in the conductive time of the interrupter switch or the increase in the closure angle relative to that determined on the basis of the on/off time of the trigger circuit is very limited and the circuitry of the control stage requires a substantial amount of additional components and is therefore relatively expensive.